Method of applying coatings to parts of rubber articles



Oct. 18, 1938. v A. L; DILLER AL 2,133,346

METHOD O APPLYING COATINGS TO PARTS 0F RUBBER ARTICLES 'Fileduarch 25,leseg 2 sheets-sheet 1 oci. 18, 193s.

A. L. DILLER ET AL 2,133,346;

METHOD OF APPLYING COATINGS TO PARTS OF RUBBER ARTICLES Filed March 25,195s `2 sheets-sheet 2 J2-Hf 51722755 Patented oei. 18, 193s UNITEDSTATES PATENT oFFicr.

METHOD F APPLYING COATINGS T0 PARTS OF RUBBER ARTICLES Application March25,

3 Claims.

This invention relates to methods kof applying coatings to parts ofrubber articles and is especially useful where coatings deposited fromlatex or aqueous dlspersions of rubber are to be applied to the uppersof rubber shoes or similar parts of rubber `articles.

It has been found that the uppers of rubber shoes, especially where suchuppersdo not contain reinforcing layers of textile material, have l0 essof vulcanization. Such sagging of the uppers may be prevented byapplying a layer of latex or other natural or artificial dispersion ofrubber to the inner surface of the uppers at such places as sagging isliable to occur, as the coating deposited from a dispersion of rubbertends to shrink during vulcanization and counteracts the tendency of thecaledered rubber to soften and stretch.

The principal objects of the present invention are to provide a methodof applying such coatings with neatness, simplicity and efliciency whileprotecting the outer surfaces of the upper fromA being soiled.`

Other objects will appear from the' following description and theaccompanying drawings.

Of the drawings:

Fig. 1 is a perspective view showing two vamps plied fa'ce to face landa coating being applied to abortion of the back of one vamp by sprayingthrough a template, part of the template being broken away.

Fig. 2 is a longitudinal section through the toe of` a shoe showing thecoating on the inner face of the vamp.

Fig.. 3 is a perspective view illustrating two sheets of vamp materialvlaid face to face and cut seamed to provide a pair of vamps.

Fig. 4 is a section taken on line 4-4 of Fig. 3.

showing the step of coating a pair of doubled vamps. i p

Fig. 6 isV a perspective view of the doubled vamps with the coatingapplied thereto and illustrating the separation vof the Vamps. l

Fig. 7 is a sectional elevation of a dipping tank showing a completeupper being dipped while supported on a form. v

Fig. '8 isa sectional view of Fig. 7.

Referring tothe drawings, in which the method is illustrated as used inthe coating of sheet rubber parts of the rubber shoes, the method of theinvention generally comprises laying sheets of the material face to faceand cutting the parts taken on line 8-8 a tendency to sag from the lastsduring the proc- 1iig. 5 is a sectional elevation of a dipping*v tank1936, Serial'No. '10,750

in pairs therefrom and then coating exposed surfaces thereof while theparts protect the finished -faces of each other from being soiled.

Referring first to Figs. 3 and 4, two layers of material I Il, II,suitable for forming a rubber I! shoe upper,'and each of which consistsof one, or more plies vof rubber material, are laid together face toface, and their faces are prevented from sticking together by a layer ofdust I2,

such as starch. By means of a suitable die, the 10 l sheets are cutsimultaneously to form a .pair of shoe parts I3, I 4 and, at the sametime, they are temporarily united along the line of cut, as at I5. 'Ihisprovides for the protection of the finished face of` each part. A layerI6 of 15 rubber may then be deposited on the exposed faces of the partsby means of a spray gun Il.

When it is desired to confine the sprayed deposit to algiven area of thepart', a template I8 may be used, as in Fig. l, to fadditionallydeflne20 the area of the deposit. In this manner the portion of a shoe uppermost liable to sag from the last duringl vulcanization, as the portionadjacent the toe, may be coated on its inside surface. Such an upper,with the layer I6 of de- 25 posited rubberis shown in Fig. 2 as builtinto a shoe.

'I'he shoe parts mayalso be coated at the toe part by dipping,as'illustrated in Figs. 5 and 6.

In practicingthe invention in this form, the sheet 80 rubber parts,united around their edges and made as shownin Figs. 3 and 4, are dippedin a tank I9 containing a natural or artificial dispersion of rubber 20,and a coating 2i of rubber is deposited thereon. The surfaces of thesheet rub- 35 ber parts in contact with'each other are protected fromthe coating dispersion. After the coating 2| has dried, the parts I3, I4may bev separated from each other. Where it is desired to coat an entireshoe up- 40 per over substantially its entire surface, the upper may beformed of a pair of blanks 22, 23, cut-seemed together about theirmargins. For convenience, a fiat sheet metal form 24 fitted with aconvenient handle 25 may be placed be- 45 tween the blanks either beforethey are seamed or afterwards by inserting the form between unseamedmargins at one edge of the blanks, and used to support the blanks duringthe dipping operation.

We claim:

1. 'I'he method of preparing articles of unvulcanized sheet rubber whichcomprises laying two sheets of rubber material in face to face relation,cutting a pair of similar articles from BI line of cut to preventsoiling of their contacting faces, applying a coating to at least a-Apart of the exposed faces of the articles, and separat-y ing thearticles from each other.

2. The method of preparing articles of unvulcanized sheet rubber whichcomprises laying two sheets ofl rubber material in face to facerelation, cutting a pair of similar articles from the two sheets andsimultaneously and temporarily seaming them'to each otheralong the lineof cut to prevent soiling of their contacting faces, dipping theattached sheets in a dispersion of rubber to apply a coating to at leasta part of the exposed surface of the articles, and separating thearticles from each other.

3. The method of preparing articles of unvulcanized sheet rubber whichcomprises laying two sheets -of rubber material in face to 'facerelation, cutting a pair of similar articles from the two sheets andsimultaneously and ternporarily seamng them to each other along the lineof cut to prevent soiling of their contacting faces, spraying theattached sheets with a dispersion of rubber to apply a coating to atleast a part of the exposed surface of the articles, and separating thearticles from each other.

ALVIN L. DILLER. FREDERICK F. OLSON.

